This is about the plan to take control of the DNS root away from the IANA and give it to a more multinational group, which could be bad but is probably more likely to be a non-issue in terms of actual day-to-day operations: It’s unlikely to make things better or worse overall.
The DNS service is like a phone book: DNS servers, when asked, map domain names like ‘www.google.com’ to IP addresses like 2607:f8b0:400a:805::1012 and 220.127.116.11 and 18.104.22.168. It’s still possible to access a website even if it isn’t in the DNS system, just like you can still call a phone number that isn’t in the phone book. You have to know the IP address but beyond that everything works the same way.
The entity that controls the DNS root can influence, but not control, which domains DNS servers can resolve. DNS servers ask each other about how to resolve domain names all the time, and specific servers can be configured to ask or not ask specific other servers about specific domains. In short, if Russia exerts its power to censor the DNS root, non-Russian DNS servers won’t ask Russian ones how to resolve names, and generally the censorship will stay contained to Russia. Which sucks if you’re Russian, of course, but that’s true today.
Some countries already censor the Internet. Censoring DNS is already part of that. It’s, sadly, nothing new, and this change won’t make it any worse.